Better, more official Summary:
Minato, Seo, and Sanada agree to form an alliance and they board the big cruise ship where the fourth round is taking place. Seo and Sanada brought all their Sekireis, but Minato only brings Kusano along. Beforehand, the group talked at Izumo Inn. Matsu posed a question of what happens if the battle is a free for all which would mean every Ashikabi for himself/herself. Musubi suggest that they can play dead, and Matsu actually thinks it's a feasible idea.
Onboard the ship, Seo, Sanada check out the competition and notice that Mikogami and Higa are missing. All the other teams are Ashikabi-Sekirei couples. Seo chats with Minato about the jinkis and reveals that Miya's husband Takehito died because of the jinkis.
Back at Izumo Inn, Miya wonders if she should start doing something, but Matsu is afraid that Miya on the move would attract Karasuba. Meanwhile, Musubi and Tsukiumi are standing on the roof ready for action.
On the cruise ship, Minaka announces that this is the last battle of the Third Stage of the Sekirei Plan and that the cruise ship will only return to port once the battle is over. On a corner of the ship, Yukari is feeling seasick. Yukari and Shiina are then approached another girl Ashikabi/ girly-boy Sekirei pair who want to take the title of Demon and Death from Yukari and Shiina.